1. Field of the Invention
The present invention relates to a camera having a variable photographing aperture and a control method thereof.
This application is related to the commonly assigned application U.S.S.N. 672,901, the disclosure of which is expressly incorporated by reference herein.
2. Description of Related Art
Cameras in which a photographing aperture can be changed between a standard size (i.e., full size) and a laterally elongated size (i.e., panoramic size) are becoming popular. Cameras employing a photographing aperture changing mechanism are usually provided with a program shutter, in which exposure factors are automatically set in accordance with the brightness of an object to be photographed. However, in conventional cameras, there is no relationship between the setting operation of the exposure factors and the changing operation of the photographing aperture.
If the setting operation of the exposure factors were to be associated with the changing operation of the photographing aperture, a picture could be photographed which satisfactorily reflects a photographer's intention. In a known camera having a photographing aperture changing mechanism, a panoramic size picture of an object can be photographed which has a lateral length longer than the standard size picture. Accordingly, a photographer can accommodate a scene that is much wider than it is high. Such a picture may include only objects that are located in an infinite object distance range, but usually includes objects located at various distances. For example, large number of people are to be photographed, they may all be located at substantially the same distance, but are usually located at different distances. Under such circumstances, it is preferable that the exposure factors are set so that the depth of field for the panoramic photographing aperture is deeper than the depth of field for the standard photographing aperture.